\begin{pspicture}(0,-0.5)(12,12)
  \input{fig/2d-helpers.tex}
	% Triangles
	\pspolygon*[linecolor=lightgray,fillcolor=lightgray]
						 (5,2.5)(8.5,6)(5,9.5)(1.5,6)
	\pspolygon[linecolor=black,linestyle=dashed]
					  (6,2.5)(9.5,6)(6,9.5)(2.5,6)
	% The TM grid.
	\multiput(1,0)(2,0){5}{%
		\multiput(0,1)(0,2){5}{%
			\hn11z{hz} 
			\en10x{ex-} \C{ex-}{hz}
			\en12x{ex+} \C{ex+}{hz}
			\en01y{ey-} \C{ey-}{hz}
			\en21y{ey+} \C{ey+}{hz}
		}
	}
  % Axes.
	\Yaxis01{11}\Xaxis1{11}0 
\end{pspicture}
